I'm quickly learning my glass, but since I keep spending my money on insulators instead of insulator books, I still know very little about porcelain. Can anyone tell me what this piece is? I can't find any markings on it, neat glaze though. Measures 6 inches high, Top Ring is 9 inches in diameter, the second ring from the top is about 1/16 inch under 7 inches. (looks like the bottom ring but you can see it's actually resting on a much smaller inner skirt).

Thanks!